Presently, mobile concrete pumping vehicles and stationary concrete pumping units are available that include a multi-section, rotatable boom arm that is folded into a compact condition during transport and storage. Once the pumping unit is positioned at the work site, the folded boom arm is extended to supply concrete to a remote location. Typically, the boom arm includes a steel boom pipe made up of multiple sections that are supported by the boom arm such that a concrete can be supplied to a remote location on the work site. The boom arm has a cross-sectional area that decreases in size as it extends further away from its center of rotation. The boom arm is designed with a maximum weight-carrying capacity that includes concrete in the boom pipe plus a factor of safety that takes into account dynamics, wind loading, etc. The weight-carrying capacity also takes into consideration the maximum weight that can be suspended from an outermost or tip section of the boom arm in the form of an end hose or “elephant trunk” filled with concrete. The load imposed by the filled end hose is typically between 200 and 400 pounds. Such boom arms are designed for general pumping applications and normally perform well in such capacity.
However, in some applications, it is deemed necessary by the user to hang tubular delivery systems that are heavier and longer than the normally used boom tip section weight. Because the tip section has the weakest cross-section and is holding weight a high moment distance from the center of rotation, the tip section is often removed and the tubular delivery system is then hung from the preceding boom arm section. In general, this has been done by the user without the manufacturer's approval in an improvised manner. If the boom arm design, pipeline support and pipeline coupling designs are not well understood by the modifying user, this can create serious loading problems that can damage the boom arm.
For example, a standard boom arm design may use an end hose that is 5 inches in diameter and 10 feet long. Removing the boom tip section and replacing the standard 10 feet end hose with a 3 foot long, 5 inch to 4 inch steel reducer pipe and 80 feet of 4 inch diameter pipe could seriously compromise the integrity of the boom arm during operation. A particular problem may occur if the boom operator causes contact of the 80 foot pipe with a local structure or by hitting the sidewall of a hole into which the filled pipe is inserted. This creates a side load on the boom arm that could slew the boom sideways in a precarious manner.
Therefore, there is a need to provide a support device that replaces the tip section of a standard boom arm and allows the boom arm to support an overweighted or oversized tubular delivery system other than the standard delivery hose. Further, there is a need to provide a support device for a tubular delivery system on the end of a boom arm in a manner which will preserve the integrity of the boom arm during any operational movement thereof.